It depends on a recent body of work which suggests that the brain's white matter (the wiring that connects the main bodies of the nerve cells, or grey matter, together) is less dense and less abundant in the brain of an autistic person than in that of a non-autist.

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This is done by examining the combined concentration of gray and white matter, or nerve cells and fiber tracts, in parts of the brain not normally used for verbal processing the hippocampus and cerebellum, normally associated with memory and motor learning.

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One study modelled the amount of exposure to organophosphates (another kind of AChEi) received by veterans and found that higher estimates of exposure are associated with greater losses of the brain's white matter.

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They found at least 5% lower concentrations of N-acetyl-aspartate in two key areas of the brain, the basal ganglia and frontal white matter.

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One experiment measured the brain structure of pathological liars, and compared it to normal controls more specifically, the ratio of gray matter (the neural tissue that makes up the bulk of our brains) to white matter (the wiring that connects those brain cells).

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